1. Field of the Invention
The present invention relates to multi-way operation switches, typically for operating vehicle electronic apparatuses, and input devices and input units employing multi-way operation switches.
2. Background Art
Increasing numbers of electronic apparatuses such as air conditioner and audio equipment are being installed in vehicles. Input devices with a plurality of switches corresponding to each specific electronic apparatus and setting mode are often installed on the dashboard. Accordingly, there is a need for a user-friendly input device that is less prone to erroneous operation.
A conventional input device of this type is described next with reference to FIG. 7.
As shown in FIG. 7, buttons 2 protrude through openings 1A on panel 1 made of insulating resin. Push switches (not illustrated) which electrically turn on and off by pushing buttons 2 are mounted at the back of buttons 2 on a printed circuit board (not illustrated).
A controller (not illustrated) configured with electronic components (not illustrated) such as a microcomputer is installed on this circuit board. The push switches are coupled to this controller to configure an input device.
This controller is also coupled to an electronic circuit (not illustrated), to which electronic apparatuses are coupled, typically via a connector. This configures the input device that transmits the ON/OFF signal of the push switches to the electronic circuit.
This input device is mounted on the dashboard facing the driver's seat. Buttons 2A and 2B for temperature control of an air conditioner output near the driver's seat, buttons 2C and 2D for adjusting the navigation display, buttons 2E and 2F for adjusting sound volume, and buttons 2G and 2H for temperature control of an air conditioner output near the passenger seat are disposed respectively in columns along panel 1. In FIG. 7, these buttons are indicated as TEMP1, NAVI, AUDIO-VOL and TEMP2.
In the above configuration, the user first needs to select button 2A among buttons 2A to 2H, for example, to increase the temperature of the air conditioner output near the driver's seat. When the user pushes button 2A, electrical connection of the push switch coupled to button 2A at the back is turned on or off. This ON/OFF signal is output from the controller to the electronic circuit in the vehicle, and finally the set temperature of the air conditioner output near the driver's seat increases.
To decrease the set temperature, the user selects and pushes button 2B underneath button 2A. This transmits the ON/OFF signal of an electrical connection corresponding to button 2B to the electronic circuit, and the set temperature of the air conditioner output decreases.
In the same way, the temperature of the air conditioner output near the passenger seat is controlled by pushing button 2G or 2H. The display screen of the navigation system is enlarged or reduced by pushing button 2C or 2D, and the sound volume is adjustable by pushing button 2E or 2F.
To change the sound volume of audio equipment, the user selects button 2E to increase the volume or button 2F to reduce it, and adjusts each setting mode by pushing these buttons.
In other words, a plurality of buttons 2A to 2H are provided individually for electronic apparatuses such as air conditioner and audio equipment, and for individual settings such as temperature and sound volume. The user can adjust the mode of the required apparatus by selecting the required button and pushing it.
This type of operation panel for vehicles is disclosed in the Japanese Patent Laid-open Application No. H8-318729.
A multi-way operation switch typically for controlling a car air conditioner is disclosed in the Japanese Patent Laid-open Application No. 2001-266712.
In the above conventional switch devices, a button and push switch are provided for each type of electronic apparatus such as air conditioner and audio equipment or for each setting mode, such as temperature and sound volume. Accordingly, the size of the input device becomes larger with increasing number of types of apparatus to be operated or setting modes for each piece of apparatus. Moreover, the operation is bothersome and erroneous operation is likely to occur, since the button to be pressed needs to be visually checked and operated every time. A switch device that can be more easily operated by drivers, in particular, is therefore needed.